Metal coating composition and method of coating



United States Patent 2,992,948 METAL COATING COMPOSITION AND METHOD OF COATING Michael W. Freeman, 1810 Wellesley Drive, Detroit, Mich. No Drawing. Filed Nov. 24, 1958, Ser. No. 775,739

. 12 Claims. (Cl. 148-624) This invention relates to the treatment of fabricated ferrous metal machine elements to increase their resistance to scuffing, scoring and seizing when utilized under operating conditions including high pressures and temperatures, to compositions for such use, and to the resulting treated articles.

Machine elements using the term in a generic sense, under service conditions are subject to deterioration in one or more of many aspects including scuffing, scoring, seizing. Thus in development in structure and design of modern engines and machines, such increased power and speed has resulted that previously suitable extreme pressure lubricants designed to lubricate and prevent damage to movable machine parts are frequently entirely useless for lubrication of modern machines, especially during the breaking-in period. Thus due to the inability of lubricating materials to withstand extreme pressure and/or severe conditions developed in the engine or machine during operation, hypoid gears, pistons, piston rings, cylinder Walls, cam shafts, as well as other essential parts of the engine are severely dam-aged or fail completely. Similar considerations apply to moving parts in other combinations and especially where free lubrication is contra-indicated, as for example, in connection with hinges, particularly for automobile doors, shock absorbers, pistons, piston rod guides, aluminum pistons and rings, piston rods, etc. Further, treating compositions heretofore used in the art have resulted in substantial etching of the metal surfaces undergoing treatment.

Among the objects of the present invention is the treatment of machine elements to modify their surface characteristics so that damage due to scoring, scuffing, seizure, etc. is avoided during the breaking-in period or subsequent period of use.

Other objects include the treatment of such machine elements to produce a tenacious integral chemical film or coating on the frictional surface without etching which film will not rupture under even the most severe operating conditions.

Other objects include the production of such surface modification without etching by treatment of the machine elements with organic sulfonic compounds or their derivatives, to produce the results set forth.

Further objects include the production of modified machine elements that may more efficaciously be used in or under operating conditions with improved results when lubricated by any suitable lubricant having extreme pressure characteristics so that the machine elements will not score, scuff or seize even under the most severe conditions.

Still further objects include methods for producing mediums which enable machine elements to be treated and modified in accordance with the present invention.

Still further objects include the treated or modified machine element itself.

Still further objects and advantages of the present invention will appear from the more detailed description set forth below, it being understood that such more detailed description is given by way of illustration and explanation only, and not,by way of limitation, since various changes therein maybe made by those skilled in the 'without departing from the scope and spirit of the present invention.

.This application is a continuation-in-part ofapplication Serial No. 262,645, filed December 20, 1951, now abandoned, entitled Metal Treatment, Articles, Compositions and Methods.

In accordance with the present invention, fabricated met-a1 machine elements, particularly ferrous metal elements which etch in aqueous solutions of sulfonic acids containing more than 50% by Weight of water which elements are in condition Without further metal working for use under extreme pressure conditions normally cansing wearing, scoring, and sentfing are treated at a temperature of about 30 C. to about 200 C. for a time of about ten minutes to about twenty-four hours in a treating medium of water and an organic sulfonic acid component, the latter being desirably neutralized at least in part by tri-ethanolamine, the water constituting by weight more than about 5% but not above about 40% of the composition, to modify the wearing pressure surfaces of the elements so that they will withstand extreme pressures and loads without any substantial etching of the metal of the element taking place.

The term machine element is used to cover all kinds and manner of such elements which are used under operating conditions where frictional forces come into play and include for example, gears, pistons, piston rings, cylinder walls, cam shafts, engine parts generally, hinges, shock absorber parts, shafts, pinions, pump parts, bearings, journals, dies for drawing, machining and stamping, etc. Such elements are principally of ferrous or ferrous alloy type but various features of the invention are applicable to other metals and metallic alloys besides irons and steels including copper, bronze, aluminum, etc. As exemplary of the effects obtained in treatment, ferrous and ferrous alloys will be utilized to illustrate the invention below.

The treatment is carried out by the use of a treating agent containing as the essential materials, water and an organic sulfonic acid, the amounts of water being critical. It has been found that to get sufficiently rapid production of substantial effect on the metal, there should be at least 5% by weight of water in such composition; But a critical upper limit exists for the amount of water present in ratio to the sulfonic acid beyond which upper limit the compo sition exerts an etching action on the metal which if substantial, is highly undersirable and generally deleterious.

.The extent of etching necessarily depends on the particular composition used, the nature of the metal part being treated, time, temperature, and other factors. As a general rule, an amount of 40 or 50% by weight of water should not be exceeded, particularly when treating conventional machine elements such as the usual ferrous metal machine elements of automobiles.

Desirably the treatment of the machine element is carried out with heating, but the temperatures employed should not be sufiicient to cause undesirable efiects either on the treating medium or on the metal treated. Since many of the treating agents ntilizable in accordance with the present invention are prepared at elevated temperature or are resistant to elevated temperatures, higher temperatures may be employed in the treating bath with such agents than with those which are susceptible to nudesired reaction or which give undesired effects on the metal or result in too rapid action. The length of such treatments will thus vary with different circumstances and media and metals and may vary from a few minutes to several hours. The temperatures employed need not be more than moderate temperatures, as for example, of the order of 30 C. to 200 C. or may be substantially higher than 200 C. Under some conditions, room temperatnre may be used. Unless undesirable reactions take place, as a general rule shorter treatment periods at elevated temperatures and higher concentrations of treating agent may be employed as compared with slower and longer treatments at lower temperatures, or where the treating agent is present in minor amount in a large amount of inert carrying medium. Thus temperature of treatment, and length of time of treatment, are usually inversely proportional to one another.

The organic sulfo compounds that may be employed include particularly the sulfonic acids and may be aliphatic, aromatic, carbocyclic, alicyclic, and heterocyclic. Generally the organic sulfonic acids may be considered primarily from the standpoint of those of the aromatic hydrocarbons and those of the aliphatic series. Either or both may be utilized in carrying out the present invention for purposes set forth above but the sulfonic acids of the aromatic hydrocarbon series are more readily available. The sulfonic acids employed may be those produced from individual hydrocarbons or mixtures of hydrocarbons or may be those derived in the purification or treatment of petroleum fractions and distillates such as petroleum sulfonate's including the mahogany acids and the green acids. Exemplary sulfonic acids that may be employed include hexane sulfonic acid, arnyl sulfonic acid, mono chloro amyl sulfonic acid, benzene sulfonic acid, phenol sulfonic acid, naphthalene sulfonic acid, heptane sulfonic acid, acetone disulfonic acid, dichloro amylene sulfonic acid, alkyl sulfonic acid, myristic sulfonic acid, stearic sulfonic acid, anthracene sulfonic acid, the sulfonic chlorides, disulphonic dinaphthyl methane, tris'tearin sulfonic acid, amylum sulfonic acid, spermaceti sulfonic acid, petroleum sulfonates such as the mahogany sulfonates and sulfonic acids, diphenyl parasulfonic acid, polyalkylated diphenyl sulfonic acid, polyalkylated naphthalene sulfonic acids, sulfonated castor oil and similar materials, sulfo dicarboxylic acids. The benzene sulfonic acid is exemplary of other monocyclic aryl sulfonic acids such as toluene sulfonic acid, etc.

While the sulfonic acids may desirably be employed as set forth above, their esters, salts and amides may also be used. Such compounds are those formed by complete or partial reaction with the sulfonic acid group. Thus, metal salts e.g. light or heavy metal sulfonates may be used. Water soluble salts may be used or they may be used in the form of oil soluble salts, particularly when oils are present in the composition. Organic salts by complete or partial neutralization of the sulfonic acid group with amines or alcoholamines may desirably be employed. The compounds, in which tri-ethanolamine has been used to at least partially neutralize the sulfonic acid group, are particularly useful in the present invention.

Amines which may be used for partial or complete neutralization of the sulfonic acids are illustrated below. Two types of reaction products may be formed. They may be salts produced by neutralization of the acid radical by an amino group, or amides be utilized in the form of sulfonamids.

Such amines include aliphatic, carbocyclic, and heterocyclic amines and exemplary amines are as follows: diethylamine, monoamylamine, diamylarnine, tr-iamylamine, di-n-butylamine, monobutylamine, dibutylamine, undecylamine, oleylamine, myristic amine, palmityl amine, stearylamine, mono-, diand tri-ethanolamine, laurylamine,

palmitylolamine, stearylolamine, ethylene diamine, di-

arnino isopropanol, cyclohexylamine, dicyclohexylamine, benzylamine, morpholine, piperidine, pyridine, quinoline, quaternary ammonium hydroxides, etc. These amines may be added at any time either during the reaction when reaction products are being produced as set forth above, or after the reaction has been completed, They have a marked tendency to inhibit corrosion, and therefore, may desirably be included with any of the materials and compositions set forth above. The organic base or mixtures of them may be selected to exhibit in addition, the property of absorbing or removing gases such as hydrogen sulfide, sulfur dioxide, and other acidic gases that may be present in the atmosphere,

or those that may form in situ. Exemplifying this fea ture, the triethanolamine referred to above will function in this way. The amounts of amines employed will vary with circumstances. When used to neutralize or partially neutralize the sulfonic acid, the amount is metathetically determined depending on whether allor onehalf, or one quarter of the acid is to be neutralized.

As to esters of sulfonic acids, these may be those commonly available in the art and produced from alcohols and phenols. The alcohols generally used are the alkyl alcohol esters, the alcohols desirably being higher alcohols as from six to twelve carbon atoms but include the higher fatty alcohols such as stearyl, palmityl, oleyl, etc. Phenol esters may be those from mono and polyhydric phenols.

As an example of one method of producing a satisfactory sulfonic material, commercial benzol which may contain toluene, xylol, phenol, and other compounds may be treated as follows:

Example A The commercial benzol is sulfonated with fuming or concentrated sulfuric acid, the mixture being subjected to elevated temperatures. Starting with a definite weight of concentrated or fuming sulfuric acid, say mole weight, heated gradually, commercial benzol is added either in the liquid or vapor state to the extent of about 50 to 70 mole weight until approximately from one-half to three-fourths of the sulfuric acid is reacted with the benzene to form benzene sulfonic acid and a mixture of other sulfonic acids Where other materials as indicated above are present. To the sulfuric acid benzene sulfonic acid mixture, commercial naphthalene is added until about 50% of the remaining free sulfuric acid reacts with it to form naphthalene sulfonic acid. In production factory test runs, the crude naphthalene employed in the above mixture was approximately 50% naphthalene, 20% phenanthrene, 10% carbazole, and 20% anthracene. To this was added about 4 mole weight of phosphorus pentoxide to take up the water of reaction, and with continued heating the resultant composition of sulfonic acids was substantially free from sulfuric acid.

In passing, it may be stated that the chloro benzene, chloro naphthalene, stearin, spermacetic, stearic acid, and the like were used in a manner similar to that just described with extremely satisfactory results. In any of these cases where sulfonic acids are present, any free sulfuric acid may be eliminated in a variety of ways as by neutralization, precipitation as an inorganic compound, etc. While phosphorus pentoxide has been suggested as a dehydrating agent, other dehydrating agents may be employed such as phosphorus pentasulfide and the like.

However, where the phosphorus pentoxide is utilized, the

phosphorus may serve additionally beyond its dehydrating function merely, either to catalyze the surface reaction or may form a phosphoro-metal compound with the surface, etc. Any neutralization which is utilized to eliminate unreacted sulfuric acid or to reduce the amount present may be carried out by utilizing inorganic bases such as the alkalis, oxides, hydroxides, and carbonates or organic bases such as aniline and other amines, alkylolamines such as the ethanolamines, etc. Other types of amines that may be employed are illustrated above in other connections and any of them may be utilized in accordance with this invention at this stage for neutralization of any free sulfuric acid present in the. sulfonic acids produced.

While as set forth above, ethanolamine neutralized sulfonic acid components are particularly emphasized, compositions in which no neutralization is employed are also usable since it is possible to obtain protective surface modification in this way. For this purpose, the fabricated Y machine elements, as described above, particularly. aqueous solutions of sulfonic acids containing moretha'n 50 %by weight'of water, which elements :are in condition without further metal working for use under extreme pressure conditions normally causing wearing, scoring and scufiing, may be treated at a temperature of about 30 C. to about 200 C. for a time of about ten minutes to about twenty-four hours in a treating medium of water and an organic sulfonic acid component, the water constituting by weight more than about 5% but not above about 40% of the composition to modify the wearing pressure surfaces of the elements. While it will be noted that these compositions are distinguished from those referred to earlier herein, by not being neutralized, all of the various modifications and variations given above, may also be included here in the non-neutralized compositions.

These organic sulfo compounds whethersulfonic acids or their derivatives may be utilized as indicated above either alone or with the organic phosphorus sulfide bodies or the inorganic phosphorus sulfide, or mixtures of them, and they may be so employed either per se where the sulfonic acid or the phosphorus sulfide modified or anic derivative is a liquid medium which also serves to carry the other materials, or these combinations of materials may be employed together with inert liquids or mediums of the character set forth above.

The organo sulfo derivatives referred to above have been indicated for utilization either with or without the inorganic phosphorus sulfides or the phosphorus sulfide modified organic bodies. Any of the indicated organo sulfo compounds including the sulfonic acids, their salts and esters may be employed in this way either individual substantially pure sulfonic acids and their derivatives, or various admixtures of such sulfonic acids with themselves and with other derivatives; and they may be so employed with water either with or without inert liquids such as various mono and polyalcohols, butyl stearate and the like or diluents being present or they may be employed in inert media of the character set forth above for use in other relations and particularly in the mineral oil or petroleum oil, their fractions and distillates to produce desirable products for treating machine elements. For example, a compatibilizing agent such as an alcoholmay be introduced to serve as an intermediary medium in such combinations with or without the additions of other amines like Alkaterge-O, (a substituted oxazoline in the form of an oil-soluble dark brown, viscous liquid), or similar materials.

As indicated, suitable compositions may be produced by dispersing or dissolving inorganic phosphorus sulfides in liquids, dispersions, suspensions, and emulsions, both aqueous and organic, with the'wate'r-sulfo compositions and utilized in the treatment of machine elements in accordance with the present invention. As exemplary of the' phosphorus sulfides that may be employed there may be mentioned phosphorus pentasulfide P 8 phosphorus sesqui'su-lfide P 8 phosphorus trisulfide P 8 phosphorus heptasulfide P 8 phosphorusdisulfide P 8 etc. As exemplary of the substantially inert liquids which may be utilized for dispersing or dissolving the inorganic phosphorus sulfide for utilization inaccordance with the present invention there may be mentioned the lower aromatic liquid hydrocarbons such as benzene and toluone, and their halogenated and similar substitution products, materials like alphachloronaphthalene, water, solutions'of inorganic bases like the caustic alkalies or of organic bases such as the amines and alkylolamines, inorganic acids such as sulfuric, hydrochloric; and nitric, or in general any diluentcapable of suspending or dispersing phosphorus sulfide so as to bring it in intimate contact with the metal surface of the machine element and thereby enable it to form the desired phosphorus sulfide protective film.

Otheridesirable compositions that can be utilized in the treatment of metal machine elements include the reaction products of a phosphorus sulfide such as those set forth above with an organic body to product a phosphorus-sulfur modified organic derivative. I A wide variety phorus sulfides. positions with the inorganic phosphorus sulfides or any of organic bodies may be utilized for modification by the phosphorus sulfide treatment including aliphatic hydrocarbons either per se or in admixtures, fatty acids particularly high molecular weight fatty acids and their esters, ketones, alcohols both aliphatic and carbocyclic, dicarboxylicacids both aliphatic and aromatic, phenols and other hydroxy aromatic compounds, such as tri chlordiphenyloxide, also including the hydroxy cyclo aliphatics like cyclohexanol, sulfonic acids both aliphatic and carbocyclic and their derivatives, mineral oil, its fractions and distillates, olefines, olefine polymers, etc.

Treating compositions as set forth above containing 1-20% by weight of inorganic phosphorus sulfides or phosphorus sulfide modified organic bodies as described above may be utilized in conjunctionwith the organic sulfo compounds which may merely be added to the mixtures containing the phosphorus sulfides or their derivatives as set forth above to produce compositions of Value. The presence of free organo sulfo compounds in such treating compositions appears to have a synergistic action and to activate the phosphorus sulfide materials to form a more tenacious chemical protective lubricating film on the metal surface.

The phosphorus sulfide reaction products of these organic bodies are generally produced at temperatures of elevated order usually running from about l50 F. to 500 F. The reaction is conducted by heating the materials together until evolution of hydrogen sulfide ceases at which time the reaction may be considered substantially complete. Where such heat treatments are carried out as with the mineral oil fractions, etc., a chemically reacted and modified product is obtained. While the mineral oil fractions, etc. may be utilized as media in which the phosphorus sulfide can be utilized in the treatment of machine elements, or with heat treatment where some phosphorus sulfide reaction product may be formed in situ and an excess of unreacted phosphorus sulfide may also be present beyond that necessary for reaction, in this invention they are used together with or as adjuncts to the water-sulfonic derivative composition because of what is believed to be a synergistic action. The amount of phosphorus sulfide employed for chemical reaction on the organic material will vary within substantial limits depending on the organic body undergoing treatment and the conditions under which the operation is carried out. Usually not more than 1 mole of phosphorus sulfide per mole of organic body need be employed and the amount of phosphorus sulfide may be substantially less. For example, not more than 50% by weight of the organic body undergoing treatment or only a fraction of a percent of phosphorus sulfide may be employed where far reaching reactions are not desired.

Where the phosphorus sulfide modified organic body is employed and is in liquid condition or is liquid at the temperature at which the treatment of the machine element is carried out, it is unnecessary to have any diluent or inert medium present with it when in the water-sulfonic derivative composition. However, the phosphorus sulfide modified organic derivatives may be utilized in media of the character set forth above for the inorganic phos- Mixtures of the water-sulfonic comof them as set forth above together with the phosphorus sulfide reaction products of the organic derivatives as set forth above or mixtures of the latter may be be used alone either in such admixtures without inert liquids or diluents or carrying mediums present or the mixtures may be employed together with inert liquids or mediums as set forth above in the treatment of the machine element. Such mixtures containing both the inorganic phosphorus sulfides'and the phosphorus sulfide modified organic bodies may be produced by utilizing an excess of phosphorus sulfide in producing the reaction product but carrying out the reaction to a point Where the organic body is modified by chemical reaction the phosphorus sulfide while still retaining an excess of phosphorus sulfide present in the mixture, and the reaction product then cooled and utilized for treating purposes as set forth herein. In all such cases, if desired, the phosphorus sulfide reaction product of the or-gano compound may be purified before use so that there is no excess of phosphorus sulfide in the final product, to give the modified organic compound per se which may be utilized as herein set forth. Or the product obtained by reacting the phosphorus sulfide with the organic body may be carried out under such conditions that reaction takes place utilizing substantially all of the phosphorus sulfide which was added to it. In any of these cases the phosphorus sulfide utilized in admixture with the phosphorus sulfide modified organic derivative may be different from that employed in producing the phosphorus sulfide modified organic body.

' While we are concerned with aqueous compositions, organic media may be added to the aqueous compositions, such organic media including mono or poly alcohols such as ethyl and other monohydric alcohols, glycols such as ethylene glycol, glycerol, sorbito-l, etc.

The medium in which the treating agent or combinations of treating agents is employed will necessarily vary when utilized depending on the nature of the treating agent or combination treating agent employed, the conditions under which it is utilized, and the metal being subjected to treatment. It should be kept in mind and emphasized that the present invention is concerned with the treatment of machine elements in their final fabricated form in condition for use without further metal working such as rolling, drawing, stamping, etc. It is the final fabricated element which is utilized in accordance with the present invention and which is subjected to the treatment to give it the properties set forth above so that such fabricated machine element is ready for use directly after the treatment without further metal working of any character. While, of course, such machine elements may after the treatment be subjected to a simple operation such as cleaning, even this is generally not necessary unless there are materials in the treating agent which should be removed to prevent further action on the metal of the machine element, or for any other reason. Consequently the medium employed for the treating agent must be chosen with these considerations in mind but generally such treating medium besides being one of the liquid treating agents as set forth above may be chosen from water or other aqueous media either alone or treated to incorporate rustproofing, non-freezing, or active ingredients such as acids, bases, etc., lipoid materials including the animal lipoids such as fats, fatty acids, etc., and the vegetable lipoids including the vegetable fats, vegetable fatty acids, etc., or combinations of them, or the vegetable, animal, and mineral oils and their various fractions and distillates or combinations of any of these stated lipoids and mineral oil fractions, as Well as organic fluids in general, both functional and non-functional such as (a) organic bases such as amines and alcoholamines or inorganic bases acting as solvents for the sulfonic materials with or without phosphorus-sulfide or to absorb gases formed, such as sulfur dioxide, hydrogen sulfide, etc., triethanolamine being exemplary, and (b) organic fluids including aliphatic, alicyclic, carbocyclic, and heterocyclic groups,'such as tricresyl phosphate, trichlorethylene, dichloro-diphenyl-oxide, glycerine, ethylene glycol, alcohols, etc., or (c) any combinations of any of these stated media many of which will be illustrated below.

These treatments in the present case should be distinguished from the prior art use of extreme pressure lubricant containing additives. Such conventional prior art extreme pressure lubricants are utilized to withstand pressures as molecular ball bearings; and the extreme pressure lubricant composition must be retained and used as such In the present invention, on the other hand,

there is accomplished a surface phenomenon, a definitive directed surface physico-c'hemicaf change" that is an integral part of the machine or other elements treated and is self-sufficient, i.e., it can function at extreme pressures in a medium ordinarily not capable of sustaining such service. The effective film thus produced on the, part in accordance with the present invention can be accomplished by heat with proper concentration of the active compound in a relatively short time, or a similar surface reaction may be effected gradually over a longer period of time at lower temperatures after which the metal surface is self-sufficient in extreme pressure service. Also it may be noted that because of their properties, the active compounds of the present case may be used as additives per se in lubricants, hydrocarbon and otherwise. The surface phenomena which come into play as a result of the present invention are not theoretical, a result demonstrated by the fact that the machine or other element is capable, as pointed out above, of functioning under extreme pressure conditions without the necessity of maintaining an extreme pressure lubricant.

In accordance with the present invention, it is believed that the surface of the metal is altered chemically and that there is formed thereon an integral thin protective lubricating film. It is further believed that there is alteration in the chemical composition of the metal surface leading to the formation of complex surface coatings or metal modified at the surface which modified surfaces possess anti-welding and anti-frictional properties. But in referring to surface modification in this way whether chemical or physical or a combination of such effects, no limitation on the invention is intended by any theoretical considerations, sincethe observed effects have been obtained regardless of the explanation offered to explain those results.

The modified surface produced on the metal machine element is in the form of an adherent film or coating resulting from the sulfonic or sulfonate treatment. It can be best referred to as a sulfonicated film or coating. This may be produced with or without other surface modifications such as a phosphosulfide coating or film resulting from the presence in the compositions of a phosphorus sulfide or a sulfur and phosphorus containing reaction product of an organic derivative, particularly where the latter is an organic sulfonic acid, or salt or other derivative thereof, particularly water miscible derivatives.

The following examples will illustrate the invention, parts being by weight unless otherwise indicated.

Example I Such sulfonic acids are desirably utilized in an aqueous medium within the limits set forth above with or without an alcohol medium, a benzene medium or various combinations thereof. As exemplary of such compositions there may be employed crude naphthalene sulfonic acid, for example, 6 denatured alcohol 50%, water 33%,%, benzene 10%, the percentages being by weight. In such types of compositions, the water may serve particularly as a medium or solvent for the sulfonic acid while the alcohol and benzene may serve in addition to dissolve any grease present on the machine element so that the sulfonic acid may more readily penetrate to the surface of the metal being treated. While alcohol and benzene may also be solvents for the particular sulfonic acid or sulfonate employed, it is not essential that all the solvents present he solventsfor the sulfonic acids in such compositions.

Example I] 25 parts of phosphorus peritasulfide dissolved 20 and then removed and utilized in accordance with the present invention. Or such compositions may beused in service in situ, or when added to a suitable medium in rear axle, hypoid, etc.

Transmission gears pretreated in accordance with the Present invention, when examined after an actual test run in an automobile engine, showed no signs of any scoring, scufiing, or seizure, while similar gears run un der the same conditions but not given any pretreatment in accordance with the present teaching, showed signs of wear, scratching, and scoring.

Other exemplary results obtained by utilizing compositions of the present invention for pretreatment of fabricated machine elements will be given below. It is not intended to suggest that each stated composition is equally as good as any other stated composition under any and all conditions. However, good results will be obtained with any of these compositions under general conditions and particular conditions may be chosen to give improved results. In some cases the results obtained were determined on an Almen testing machine designed with 30 pounds as a maximum full load. Even with full load some tested articles showed no wear at all. Some articles like gears and pinions may desirably be tested in accordance with the number of hours that they stand up under an accelerated test under actual operating conditions and compared with the conventional lubricating mediums of seven extreme pressure lubricant type, normally employed in service in that connection.

In the treatment of gears, compositions of Examples I and II gave excellent results even under full maximum load whereas comparative tests with conventional lubricant gave relatively short life and rapid failure. To illustrate some further results obtained with the composition of Example II, pinions were treated for 34 minutes in the composition of Example II at a temperature of approximately 160 C. These pinions when hooked on to a 90 HP. pump, stood up without snuffing for 93 ,4 hours against a hour test with identical gears which had not been given the treatment with the composition of Example II.

The naphthalene sulfonic acid of any of these examples may be substituted by other sulfonic acids set forth above to give comparable results.

As illustrative of the treatment of elements of the character of hinges and hinge pins, hinge pins treated with a composition of Example H stood up (when one drop of oil was introduced on the pin in order to plasticize the surface) about 200,000 cycles against about 25,000 cycles when ordinary service lubricant was used Without the pretreatment in accordance with the present invention.

Example 111 A mixture of 72 parts of sulrfonic acid complex (prepared as described above in Example A) with 28 parts of water, was used to treat various finished machined parts, such as gears, pinions, piston rings, shock absorber heads, pinions and pressure cylinders. 'I'he bath was maintained at temperatures of from 90 to 135 C. for treating times of from to 45 minutes. To determine the efficacy and and life of the bath, wedges and pins were treated and tested in the Almen machine. Exemplary results are as follows. A pin from the first bath failed at 14 pounds; one from. the fourth bath did not fail at 30 pounds; another from the sixth bath stood up the maximum load of 30 pounds. These results may be compared with failure at 8 pounds in the Almen machine for treatment with plain oil.

Example IV A mixture of 62.5 parts of sulfonic acid complex, as given in Example III, with 6.25 parts of phosphorus pentasulfide dissolved in 6.25 parts of alcohol was used. The same parts were treated as in Example III for times of 15 to 45 minutes at a temperature 30 C. to 130 C.

. r 10 The pins in the Almen machine from first bath at 16 pounds, but the bath weakened sooner than that of Example III.

Example V Pinions and ring gears for Chevrolet rear end were treated with the sulfonic acid compounds prepared as in Example A. To these sulfonic acids for every grams add 40 grams of water. The bath with the gears and pinions was heated to about to C. for a period of 75 minutes. When cooled the gears and pinions were wiped to remove the excess compound and as. such were tested to compare with non-treated gears and pinions under the same condition of testing.

Remark 1: Gears checked alter first break in and found to be good. Remark 2: Gearschecked after fifteen times running back and forth from 60 to 80 m.p.h. and found to be good.

Remark 3: Gears checked after five more shock tests from 70 to 90 mph. and found to be good.

Remark 4: Gears checked after giving additional severe shocks and found to be good.

Remark 5: After all the above tests were completed the gears were removed and washed tor inspection and found to be without any sign of wear, scufling, scoring, or seizing.

The results are very spectacular and outstanding beyond comparison.

To study conditions of wearing surfaces where stresses and strains are developed in running the moving surfaces without lubrication and in a dry state, tests were conducted by treating such parts as indicated in Example V, then covering the surface with a very light film of molyb denum disulfide, in other cases with liquid organic silicon polymer, then utilizing a combination of both by applying the film of molybdenum disulfide followed with the application of a thin film of the liquid organic silicon polymer, or in other cases the order was reversed and the organic silicon polymer was applied first then followed with the application of a thin film of molybdenum disulfide.

In other cases parts treated as in Example V were wiped with a light coat of butyl stearate, or with a polyalcohol. This is thought to be especially useful in places where dry lubrication or no lubrication is applicable.

All data below obtained on an Almen testing machine:

Squealed Torque, RanWet How samples finished at- Tailed atpounds or Dry pounds As in Example V. A. 22 Full Load..- 65 Wet.

Treated at C. for 20 minutes.

As (A) but bearing not B. 18 -do 60 Wet.

treated.

As (B) but treated sur- 0. 8 14 pounds..- 60 Wet.

face washed off.

As (A) but wiped with D. 8 14 pounds-.- 60 Dry.

Molybd. Sulfide.

As (D E. 22 Full Load.-- 60 Wet.

As (A) but wiped with F. 24 26 pounds... 60 Wet.

Organic Silicon polymer.

Same as (F) G. 24 Full Load..- 60 Wet.

As (D) then wiped with H. 14 18 pounds--- 60 Wet.

Liq. Org. Silicon polymer.

Same as (H) I. Full Load.-- 60 Wet.

Same as A) but wiped I. 24 do 60 Wet.

with Butyl Stearate.

Same as (J) but bearing K. 19 do 60 Wet.

not treated.

Same as (J) L. 10 18 pounds.-- 60 Dry.

Having thus set forth my invention, I claim: 1. The method of improving the load capacity of a aaaaeas.

iabr sa ed r m s. me al t aqli sv lem h qh e ch n aqu o solu ons. of sulfoniic i s ta ni m r than 50% by weight of water in condition without further metal working for use under extreme pressure conditions normally causing wearing, scoring and scuffing which method comprises treating said element at a temperature oi ahout30 C. to about 200 C. for a time of about ten minutes to about twenty-four hours, the temperature and length of time of treatment being inversely related, in a treating medium consisting oi water and an ethanola-mineorganic sulfonic acid component, the water constituting by weight more than 5% but not above about 49% of the composition, to modify the wearing pressure surfaces of the element to withstand extreme pressures and loads without any substantial tchin f the meta Qi the element 2. The method of claim 1 in which the sulfonic acid component is a sulfur and phosphorus containing reaction product of a phosphorus sulfide and an organic sulfonic acid which reaction product is at least in part neutralized with triethanolamine.

3. The method of claim 2 in which a hydrocarbon lubricating oil is added to the treating medium.

4. The method of claim 1 in which the triethanolamine is any alkylolamine.

5. The method of claim 4 in which the sulfonic acid component is a sulfur and phosphorus containing reaction product of a phosphorus sulfide and an organic sulfonic acid which reaction product is at least in part neutralized with an alkylolamine.

6. The method of claim 5 in which a hydrocarbon lubricating oil is added to the treating medium.

7. A composition for improving the load capacity of a fabricated ferrous metal machine element which etches in aqueous solutions of sulfon-ic acids containing more than 50% by weight of water, in condition without further metal working for use under extreme pressure con- 12 di i ss n rm l au in weari win and swfi s s i om os ti n con i ing wa e a st 'sttiss s a cen rali e a ic lfo a id qmr ne a he at being neutralized at least in part by triethanolamine the a wa r w s iw ssby w h mo han 5 but PO? m than about 40% of the composition.

'8. The composiion of claim 7 in which the sulfonic acid component is a sulfur and phosphorus containing reaction product of a phosphorus sulfide and an organic sulfonio acidwhich reaction product is at least part neutralized with triethanolamine.

9. The composition of claim 8 in which a hydrocarbon lubricating oil is added to the composition.

10. The composition of claim 7 in which the triethanolamine is any alkylolamine.

11. The composition of claim 10 in which the sulfonic acid component is a sulfur and phosphorus containing reaction product of a phosphorus sulfide and an orgahic sul fonic acid which reaction product is at least in part neutralized with an alkylol-amine.

12 The composition of claim- 11 in which a hydrocarbon lubricating oil is added to the composition.

References Cited in the file of this patent OTHER REF R NcEs Pritzker: Use of Phosphorus Sulfide Organic Reaction r Products as Lube Oil Additives, National Petroleum News, December 5, 1945, pages R100l, R-100;2,R-1Q06,, R=l004, R-l008-Rr10l0. 

1. THE METHOD OF IMPROVING THE LOAD CAPACITY OF A FABRICATED FERROUS METAL MACHINE ELEMENT WHICH ETCHES IN AQUEOUS SOLUTIONS OF SULFONIC ACIDS CONTAINING MORE THAN 50% BY WEIGHT OF WATER IN CONDITION WITHOUT FURTHER METAL WORKING FOR USE UNDER EXTERME PRESSURE CONDITIONS NORMALLY CAUSING WEARING, SCORING AND SCUFFING WHICH METHOD COMPRISES TREATING SAID ELEMENT AT A TEMPERATURE OF ABOUT 30*C. TO ABOUT 200*C. FOR A TIME OF ABOUT TEN MINUTES TO ABOUT TWENTY-FOUR HOURS, THE TEMPERATURE AND LENGTH OF TIME OF TREATMENT BEING INVERSELY RELATED, IN A TREATING MEDIUM CONSISTING OF WATER AND AN ETHANOLAMINENEUTRALIZED ORGANIC SULFONIC ACID COMPONENT, THE WATER CONSITUTING BY WEIGHT MORE THAN 5% BUT NOT ABOVE ABOUT 40% OF THE COMPOSITION, TO MODIFY THE WEARING PRESSURE SURFACES OF THE ELEMENT TO WITHSTAND EXTREME PRESSURES AND LOADS WITHOUT ANY SUBSTANTIAL ETCHING OF THE METAL OF THE ELEMENT. 